Underworld Emperor created War Secret Technique. He is Cao Yusheng’s second life.

Underworld Emperor is also called Source Emperor. He realized his Dao thru dead body and source technique.

He built a prefecture in the underworld to echo the celestial court of his disciple : Emperor the Venerable.

Ye Fan in “Shrouding the Heavens”

War Secret Technique can be used to manipulate weapons. It can also be used to manipulate opponent as weapons.

Ye Fan got this secret technique from Middle State Cai Family’s no name mountain.